This invention relates generally to flow control devices and more particularly to a combined clamp and flow control which exerts a compressive force on a length of tubing over a wide area so as to prevent permanent crimping of the tubing, and which provides separate controls for gross and fine regulation of the flow of liquid through the tubing.
Clamping devices, or fluid flow control units of the type concerned with in this invention, are disclosed in U.S. Pat. Nos. 2,595,511 and 3,099,429. In these units, rollers are employed to exert an increasing or decreasing force upon flexible tubing so as to control the flow of liquid therethrough.
U.S. Pat. No. 3,960,149, of the present inventor discloses a combined clamp and flow control member which utilizes a rotatable member movably positioned within a clamp so as to exert a compressive force against a platen and thereby against a piece of flexible tubing. As a result, flow of liquid through the tubing is controlled. The present invention represents a distinct improvement over applicant's previous patent in that separate means are provided for coarse and fine regulation of the flow of liquid through the tubing. As a result, a greater number of incremental flow control settings are available than similar devices in the prior art.